Snap lines have been used in the construction industry for many years for laying out building or dimensional lines. They are easy to use, accurate, and inexpensive. Typically, a snap line is tautly held adjacent or slightly above a surface that is to be marked. The line is then pulled away from the surface and released so that it strikes against the surface, leaving a residual line of powdered material, such as chalk. Over the years, snap line technology has evolved; powdered material is now available in colors other than blue, and housings are better able to retain and protect the powdered material from the elements.
One thing that has not changed over the years, however, is the use and operation of the snap line. That is, the snap line must still be positioned adjacent or slightly above a surface to be marked, pulled away, and then released so that it strikes against the surface to be marked. This works quite well for most surfaces. However, a drawback with existing snap lines is that they are ineffective when weather conditions are less than ideal.
As one may expect, conventional snap lines often do not operate as intended when conditions are wet or damp. Often, the powdered material adheres to the snap line and does not release when the line strikes the surface. Moreover, if some of the powdered material does manage to release from the line upon impact, it does not easily transfer to a surface to be marked, and if transfer does occur, the powdered material can be easily smeared and/or washed away. Thus, whenever wet conditions exist, layout work is essentially halted. This can be problematic in areas where wet conditions such as precipitation and high humidity are common.